Pulse generators and leads having electrodes implanted in or about the heart have been used to reverse certain life threatening arrhythmia, or to stimulate contraction of the heart. Electrical energy is applied to the heart via an electrode to return the heart to normal rhythm. Leads are usually positioned on, in, or near the ventricle or the atrium and the lead terminal pins are attached to a pacemaker or defibrillator which is implanted subcutaneously. The pulse generator is configured to utilize the electrodes to receive signals from the heart which can indicate certain cardiac events.